This invention relates generally to a device for projecting and reshaping a beam of radiation. More particularly, this invention relates to a device for expanding a radiation (i.e., laser) beam, reshaping the beam into a desired cross-section (i.e., circular to rectangular), modifying the intensity distribution and projecting the reshaped beam onto a distant surface.
There is currently a need for discrete devices which expand, reshape and project beams of radiation. An example of an application which may require such a device is the imaging lidar system disclosed in U.S. Pat. No. 4,862,257 wherein a pulsed light source (laser) projects typically circular pulses of light at a target in a backscattering medium with the reflected light pulses being detected by one or more gated cameras. In certain situations, it may be advantageous to reshape the pulsed light from the original circular cross-sectional shape to another configuration, generally rectangular or square. This need is particularly important in the imaging lidar system described in U.S. patent application Ser. No. 565,631 filed contemporaneously herewith, entitled "Imaging Lidar System" and invented by Charles H. Kaman, Bobby L. Ulich, Robert Mayerjak and George Schafer Attorney Docket No. 90-1321. Presently, it is difficult to effectively and accurately expand, reshape and project radiation beams such as laser beams; and no single, discrete device is presently known which executes this type of beam modification.